<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
</head>
<body>
	<script>
		var a = [1,2,3]
		var b = a;
		b.push(4)
		console.log(a) // [1,2,3,4]
		console.log(b) // [1,2,3,4]

		console.dir(b)

		var c = a;
		c = [4,5,6];
		console.log(c) // [4,5,6]

	</script>
</body>
</html>